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Consistent constitutive modeling of metallic target penetration using empirical, analytical, and numerical penetration models

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Defence Technology（防务技术） 2016年第2期12卷 201-213页

作者： john(jack) P.RIEGEL III David davison R3 Technology Inc. 7324 Fountain Spring Ct. Shock Transients Inc.

Historically, there has been little correlation between the material properties used in(1) empirical formulae,(2) analytical formulations, and(3) numerical models. The various regressions and models may each provide excellent agreement for the depth of penetration into semi-infinite targets. But the input parameters for the empirically based procedures may have little in common with either the analytical model or the numerical model. This paper builds on previous work by Riegel and Anderson(2014) to show how the Effective Flow Stress(EFS) strength model, based on empirical data, can be used as the average flow stress in the analytical Walker–Anderson Penetration model(WAPEN)(Anderson and Walker,1991) and how the same value may be utilized as an effective von Mises yield strength in numerical hydrocode simulations to predict the depth of penetration for eroding projectiles at impact velocities in the mechanical response regime of the materials. The method has the benefit of allowing the three techniques(empirical, analytical, and numerical) to work in tandem. The empirical method can be used for many shot line calculations, but more advanced analytical or numerical models can be employed when necessary to address specific geometries such as edge effects or layering that are not treated by the simpler methods. Developing complete constitutive relationships for a material can be costly. If the only concern is depth of penetration, such a level of detail may not be required. The effective flow stress can be determined from a small set of depth of penetration experiments in many cases, especially for long penetrators such as the L/D = 10 ones considered here, making it a very practical approach. In the process of performing this effort, the authors considered numerical simulations by other researchers based on the same set of experimental data that the authors used for their empirical and analytical assessment. The goals were to establish a baseline with a full constitut

关键词：本构模型渗透模型数值模型金属靶材料性质流动应力程序模拟数值计算

Human osteoclast formation and resorptive function on biomineralized collagen

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Bioactive Materials 2022年第2期7卷 241-252页

作者： Daniel de Melo Pereira Noel davison Pamela Habibovic Department of Instructive Biomaterials Engineering MERLN Institute for Technology-Inspired Regenerative MedicineMaastricht University6229 ERMaastrichtThe Netherlands

Biomineralized collagen composite materials pose an intriguing alternative to current synthetic bone graft substitutes by offering a biomimetic composition that closely resembles native *** hypothesize that this composite can undergo cellular resorption and remodeling similar to natural *** investigate the formation and activity of human osteoclasts cultured on biomineralized collagen and pure collagen membranes in comparison to cortical bone *** monocytes/macrophages from peripheral blood differentiate into multinucleated,tartrate-resistant alkaline phosphatase(TRAP)-positive osteoclast-like cells on all *** cells form clear actin rings on cortical bone,but not on biomineralized collagen or pure collagen *** form resorption pits in cortical bone,resulting in higher calcium ion concentration in cell culture medium;however,osteoclast resorption of biomineralized collagen and collagen membranes does not measurably *** of osteoclast enzymes-TRAP,carbonic anhydrase II(CA-II),and cathepsin-K(CTS-K)-is similar on all substrates,despite phenotypic differences in actin ring formation and *** mesh-like structure,relatively low stiffness,and lack of RGD-containing binding domains are likely the factors responsible for preventing formation of stable actin rings on and resorption of(biomineralized)collagen *** insight helps to guide further research toward the optimized design of biomineralized collagen composites as a more biomimetic bone-graft substitute.

关键词： Osteoclastogenesis Osteoclast resorption Biomineralized collagen Intrafibrillar mineral Bone graft substitute

Are we really“screening”movement?The role of assessing movement quality in exercise settings

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journal of Sport and Health Science 2020年第6期9卷 489-492页

作者： Hunter Bennett john Arnold Kevin Norton Kade davison Alliance for Research in Exercise Nutrition and ActivitySansom Institute for Health ResearchUniversity of South AustraliaAdelaideSA 5001 Australia

*** The assessment of movement quality became widespread in exercise settings following the introduction of Gray Cook’s Functional Movement Screen(FMS).1 Assessing muscle and joint function during real-world movement... 详细信息

关键词： movement assessing assessed

Hepatocellular carcinoma incidence post direct-acting antivirals in hepatitis C-related advanced fibrosis/cirrhosis patients in Australia

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Hepatobiliary & Pancreatic Diseases International 2020年第6期19卷 541-546页

作者： Patrick P Y Chan Miriam T Levy Nicholas Shackel Scott A davison Emilia Prakoso Department of Gastroenterology and Hepatology Liverpool HospitalElizabeth StreetLiverpoolNSW 2170Australia South Western Clinical School University of New South WalesLiverpoolNSW 2170Australia Central Clinical School-The Faculty of Medicine and Health University of SydneyNSW 2050Australia

Background:Despite efficacy in HCV eradication,direct-acting antiviral(DAA)therapy has raised controversies around their impact on hepatocellular carcinoma(HCC)*** we reported the first Australian data on HCC incidence in DAA-treated HCV patients with advanced fibrosis/***:We conducted a retrospective single center study of DAA-treated HCV patients with advanced fibrosis/cirrhosis from April 2015 to December *** with prior HCC were included if they had complete response to HCC ***:Among 138 patients who completed DAA therapy,133(96.4%)achieved sustained virologic response(median follow-up 23.8 months).Ten had prior HCC and 5/10(50.0%)developed recurrence,while de novo HCC developed in 7/128(5.5%).Median time from DAA to HCC diagnosis was 34 weeks in recurrent HCC *** novo 52 weeks(P=0.159).In patients with prior HCC,those with recurrence(***)had shorter median time between last HCC treatment and DAA(12 vs.164 weeks,P<0.001).On bivariate analysis,failed sustained virologic response at 12 weeks(SVR12)(P=0.011),platelets(P=0.005),model for end-stage liver disease(MELD)score(P=0.029),alpha fetoprotein(AFP)(P=0.013),and prior HCC(P<0.001)were associated with HCC *** multivariate analysis,significant factors were prior HCC(OR=4.80;95%CI:1.47–48.50;P=0.010),failed SVR12(OR=2.83;95%CI:1.71–16.30;P=0.016)and platelets(OR=0.97;95%CI:0.95–0.99;P=0.009).Conclusions:Our study demonstrates a high incidence of recurrent HCC in HCV patients with advanced fibrosis/cirrhosis treated with *** associated with HCC development post-DAA were more advanced liver disease,failed SVR12 and prior HCC,with higher rates of recurrence in those who started DAA earlier.

关键词： Direct-acting antiviral Cirrhosis Hepatitis-C virus Hepatocellular carcinoma Recurrence

The Potential of Simulation to Enhance Nursing Students’ Preparation for Suicide Risk Assessment: A Review

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Open journal of Nursing 2017年第2期7卷 129-144页

作者： j.anna davison Bev Mackay Michael j. McGivern NorthTec Nursing Department Whangarei New Zealand

Suicide risk assessment is a critical skill in preventing suicide. Yet most nurses do not feel confident in assessing suicide risk. Development of this potentially life-saving skill needs to begin at the undergraduate nursing level. As simulation is an effective pedagogical tool utilised within nursing education, the aim of this paper was to explore the potential of simulation in preparing student nurses’ for suicide risk assessment. Literature was examined to identify what simulation modalities were employed within nursing education and the outcomes associated with these. The findings suggest that to varying degrees all simulation modalities have the potential to decrease student anxiety, and increase student confidence, knowledge and communication skills when working with people at risk of suicide. However the use of Standardised Patient (SP) simulation adds an authenticity to the experience and allows for the assessment of a wider range of human responses, including key nonverbal communication skills. The sense of realism provided by SP allows for more in-depth understanding into the person’s experiences, which is critical in the assessment of a person’s mental health needs and risk of suicide. The majority of simulations identified were located within a mental health setting. Given that student nurses may encounter a person who is suicidal in any clinical setting, further research is needed on simulation which integrates mental health assessments and suicide risk assessment into a variety of clinical areas.

关键词： Mental Health Student Nurses Simulation Suicide Risk Assessment

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条件数在大系统辨识数值分析中的应用

控制理论与应用 1990年第4期7卷 93-97页

作者：张红艺 E.j.davison 江西大学计算机科学系 Univ.of Toronto Canada

本文利用条件数的链式性质,研究了大系统辨识中存在的数值问题,证明了关于参数辨识问题的条件数一般随着阶数增加而严格地单调增加。

关键词：条件数大系统系统辨识数值分析

Metabolomic studies in the inborn error of metabolism alkaptonuria reveal new biotransformations in tyrosine metabolism

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Genes & Diseases 2022年第4期9卷 1129-1142页

作者： Brendan P.Norman Andrew S.davison juliette H.Hughes Hazel Sutherland Peter j.M.Wilson Neil G.Berry Andrew T.Hughes anna M.Milan jonathan C.jarvis Norman B.Roberts Lakshminarayan R.Ranganath George Bou-Gharios james A.Gallagher Institute of Life Course and Medical Sciences University of LiverpoolWilliam Henry Duncan Building6 West Derby StreetLiverpoolL78TXUK Department of Clinical Biochemistry&Metabolic Medicine Liverpool Clinical LaboratoriesRoyal Liverpool University HospitalPrescot StreetLiverpoolL78XPUK School of Sport&Exercise Sciences Liverpool John Moores UniversityTom Reilly BuildingByrom StreetLiverpoolL33AFUK Department of Chemistry University of LiverpoolCrown StreetLiverpoolL697ZDUK

Alkaptonuria (AKU) is an inherited disorder of tyrosine metabolism caused by lack of active enzyme homogentisate 1,2-dioxygenase (HGD). The primary consequence of HGD deficiency is increased circulating homogentisic acid (HGA), the main agent in the pathology of AKU disease. Here we report the first metabolomic analysis of AKU homozygous Hgd knockout (Hgd−/−) mice to model the wider metabolic effects of Hgd deletion and the implication for AKU in humans. Untargeted metabolic profiling was performed on urine from Hgd−/− AKU (n = 15) and Hgd+/− non-AKU control (n = 14) mice by liquid chromatography high-resolution time-of-flight mass spectrometry (Experiment 1). The metabolites showing alteration in Hgd−/− were further investigated in AKU mice (n = 18) and patients from the UK National AKU Centre (n = 25) at baseline and after treatment with the HGA-lowering agent nitisinone (Experiment 2). A metabolic flux experiment was carried out after administration of 13C-labelled HGA to Hgd−/−(n = 4) and Hgd+/−(n = 4) mice (Experiment 3) to confirm direct association with HGA. Hgd−/− mice showed the expected increase in HGA, together with unexpected alterations in tyrosine, purine and TCA-cycle pathways. Metabolites with the greatest abundance increases in Hgd−/− were HGA and previously unreported sulfate and glucuronide HGA conjugates, these were decreased in mice and patients on nitisinone and shown to be products from HGA by the 13C-labelled HGA tracer. Our findings reveal that increased HGA in AKU undergoes further metabolism by mainly phase II biotransformations. The data advance our understanding of overall tyrosine metabolism, demonstrating how specific metabolic conditions can elucidate hitherto undiscovered pathways in biochemistry and metabolism.

关键词： Alkaptonuria Biotransformation Metabolism Metabolomics Mice

英国Thrybergh钢厂新建棒材盘卷生产线产品质量和过程控制

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钢铁 2008年第11期43卷 103-107页

作者： K.j.davison F.Toschi G.Salvador 康力斯工程钢公司Thrybergh棒材厂达涅利摩根沙玛公司

介绍了英国康力斯公司新建大盘卷棒材生产线的主要特点和技术亮点,以及配套的先进的过程控制系统,该系统使成套设备刚一进入试车投产阶段,就能够满足产品质量要求。

关键词：棒材盘卷生产线产品质量过程控制

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载重车胎的设计与应用

橡胶译丛 1980年第5期 68-74页

作者： j. A. davison 北京橡胶工业研究设计院轮胎室

应力关系概述轮胎内部的应力不仅与轮胎结构的类型和尺寸有关,而且还与内压、变形和速度等使用条件有关。另一方面,由此而形成的应力的大小则是轮胎制造时,诸原材料和结构部件的选择依据。张应力轮胎的强度通常系与轮胎主要部件损坏前... 详细信息

应力关系概述轮胎内部的应力不仅与轮胎结构的类型和尺寸有关,而且还与内压、变形和速度等使用条件有关。另一方面,由此而形成的应力的大小则是轮胎制造时,诸原材料和结构部件的选择依据。张应力轮胎的强度通常系与轮胎主要部件损坏前所能承受的最大充气应力有关。其他一些指标,诸如轮胎损坏前所能承受的最大穿透力,某些部件对于高冲击力或者局部应力集中的耐受强度等也都可以看作为是与轮胎的强度有关的特性指标。跟轮胎的强度相关联的最重要的因素系牵涉到轮胎的一些主要结构部件、胎圈、胎体帘布层以及带束等。

关键词：帘线切应力胎冠胶料箍紧剪应力胎圈部位轮胎花纹胎面花纹带束层线张力帘布层数胎体帘布层胎侧胶轮胎结构